Slumping demand for diesel vehicles dragged down new car sales in February, marking the 11th consecutive month of declines for Britain’s new car market.

The number of new cars registered dropped 2.8% compared to the same month a year ago to 80,805, according to the Society of Motor Manufacturers and Traders (SMMT), the industry trade body. The rate of decline has slowed from the double-digit drops seen at the end of last year.

But sales of diesel cars fell by 23.5% to 28,317 last month, reducing their share of the market to 35% from 44.5% a year ago.

February is usually a quiet month before the number plate change in March, when around a quarter of all cars are registered each year. Dealers often offer discounts to sell cars with old plates.

However, the SMMT is expecting a further year-on-year drop in March, as this time last year buyers were rushing to get their new cars registered before an increase in vehicle excise duty in April 2017.

Mike Hawes, the SMMT chief executive, said:“Looking ahead to the crucial number plate change month of March, we expect a further softening, given March 2017 was a record as registrations were pulled forward to avoid VED changes.”

The SMMT said the sharp decline in diesel sales suggested owners were keeping their old cars longer. It described the slump in diesel demand as “disappointing”, given that the “latest cars are the cleanest in history and can help address air quality issues”.

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Demand for secondhand diesels has also plummeted since the Volkswagen emissions scandal erupted in September 2015. A third of VW cars that were equipped with devices to cheat emissions tests remain unfixed, it emerged in November.

Howard Archer, the chief economic adviser to the EY Item Club, said the 11th month of falling car sales pointed to a “sustained loss of momentum in the sector” – indicating that “squeezed, uncertain consumers are still reluctant to make major purchases”. Consumer spending last year likely grew at the slowest rate since 2011, he added.

The SMMT figures showed sales of petrol cars rose 14.4% year-on-year in February, taking their market share to 60.6% from 51.5%. Sales were boosted by new smaller models coming on to the market, such as the latest version of the Ford Fiesta and the US carmaker’s new SUV EcoSport.

Sales of electric and hybrid vehicles also continued to climb, rising 7.2% in February.

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So far this year, the UK new car market has declined by 5.1%, with registrations by business, private and fleet buyers all down – by 29.8%, 7.1% and 2.1% respectively.

Archer said: “Car sales are likely to be hampered by mounting pressure to restrict car finance deals and unsecured consumer credit. The Bank of England has shown mounting concern over this and is keen for a more responsible approach to be adopted. This is magnified by concerns over the resale value of cars at the end of PCP deals.”

Britain’s car industry body expects demand for new cars to fall by a further 5% to 7% this year before recovering next year, amid uncertainty caused by Brexit and the government’s diesel policy.

Robert Gordon, chief executive of motor finance provider Hitachi Capital UK, said consumer awareness of the benefits of electric and hybrid vehicles continued to grow.

“Our own research found that 82% of fleet owners believe it is important to move towards alternative-fuelled vehicles and it would appear that momentum is beginning to increase beyond the commercial vehicle sector. As this continues to develop, both the government and private sector needs to ensure the infrastructure is in place to make this a reality.”